The amount of nanoplastics in drinking water in the U.S. has been wildly underestimated. That’s according to a new study that found the amount of plastic in both tap and bottled water was 10-100 times higher than previous estimates.

For the new study, researchers used more advanced methodology and found more plastic. “It is like the difference between looking at the stars with and without a telescope,” lead author Megan Jamison Hart, an environmental science researcher at The Ohio State University, and her adviser, John Lenhart, an environmental engineering professor at the same institution, told Mongabay by email.

“Like the stars, plastics are there either way, but the analytical technique we used let us see a lot more than what previous studies have been able to quantify, similar to seeing more stars with a telescope,” they added.

They also found that concentrations of nanoplastics — particles smaller than a micron, or one-thousandth of a millimeter — were three times higher in bottled water than tap. Overall concentrations of micro and nano plastics (MNPs) were twice as high in bottled water compared with treated tap water.